ISOLATED ABERRANT RIGHT SUBCLAVIAN ARTERY: SHOULD INVASIVE INTERVENTION BE RECOMMENDED IN THE ERA OF NONINVASIVE PRENATAL TESTS?

Objective: An aberrant right subclavian artery (ARSA) is an aortic arch anomaly isolated or associated with other ultrasound markers and/or congenital anomalies. This study aimed to evaluate the necessity of invasive prenatal tests (PIT) in cases with isolated ARSA (iARSA) in prenatal sonography. Materials and Methods: The presence of ARSA was evaluated retrospectively in 7690 fetuses who underwent a second-trimester ultrasonography evaluation between March 2015 and February 2021. PIT was recommended for patients with non-iARSA. cfDNA test (including 22q11.2 microdeletion/duplication syndrome (MMS) or PIT was suggested for patients with iARSA. Results: The mean week of gestation was 20.26±3.93 in 95 fetuses diagnosed with ARSA. Of the fetuses, fourty-two (44%) had iARSA, and 53 (56%) had additional findings. No chromosomal abnormality was found in any of the isolated cases. Trisomy 21 in 14, Trisomy 18 in one, 47,XX,+i(9)(p10) in one of 53 were found in non-isolated cases. Additional abnormalities and/or soft ultrasound markers were accompanied in all fetuses with chromosomal abnormalities. Conclusion: When iARSA is detected in prenatal ultrasonography, cfDNA testing may be sufficient, including 22q11.2 MMS. However, PIT should be recommended in the presence of structural abnormalities, soft ultrasound markers, or increased risk in the antenatal screening test. [ABSTRACT FROM AUTHOR]